[Jonakss]

What happens

maxContextLimit / minContextLimit default to absolute token counts
(100000 / 50000), while both already accept a percentage of the model window.

On a 1M-token model at 250k tokens that is 2.5x the default maximum, so
isContextOverLimits() returns overMaxLimit: true on every turn and DCP keeps
injecting:

CRITICAL WARNING: MAX CONTEXT LIMIT REACHED — you MUST use the compress tool now.

…while three quarters of the window are still free.

Reproduced on OpenCode 2.2.5 with a 1M-window model at 250k tokens: the nudge
fires every turn.

Fix

Only the default changes. resolveContextTokenLimit() already resolves "X%"
against state.modelContextLimit, so the plumbing stays untouched.

File	Change
lib/config.ts	100000 → "70%", 50000 → "35%"
dcp.schema.json	the two property defaults + the compress.default block
README.md	config example, with a note on why it is percentage-based
tests/context-limit-defaults.test.ts	new regression test

A 128k window resolves to ~90k / ~45k, so small-window behaviour is preserved.
When the window is unknown the percentage resolves to undefined and the nudge
fails open instead of nagging on a guessed budget.

Untouched: nudgeFrequency, iterationNudgeThreshold, nudgeForce, and the
per-model modelMaxLimits / modelMinLimits overrides.

Verification

Case	Result
250k tokens, 1M window	overMaxLimit: false — was true, this is the bug
750k tokens, 1M window	true
80k tokens, 128k window	min only
95k tokens, 128k window	max
unknown window	false — fails open

npm test 119 → 123 pass; typecheck, build and prettier clean.

The regression test asserts the shipped defaults against dcp.schema.json and the
lib/config.ts source rather than the runtime object, because lib/config cannot
be imported under tsx (its jsonc-parser subpath exposes no named exports).
That is pre-existing and stated at the top of the test so the indirection does not
look accidental.

[Jonakss]

Heads-up: CI sequence run locally

Before opening I ran the .github/workflows/pr-checks.yml steps in the checkout:

npm ci --legacy-peer-deps    # ok
npm run format:check         # ok
npm run typecheck            # ok
npm run build                # ok
npm test                     # 123 pass
npm audit --audit-level=high # exit 1

The last one fails with the current lock: 49 vulnerabilities — 13 high, 3 critical
(@opentui/solid, seroval, solid-js).

It is pre-existing. package-lock.json is untouched in this PR:

$ git diff master...HEAD -- package-lock.json package.json
# empty

so master reports exactly the same. Not fixed here because it is a TUI dependency
bump, out of scope for this change.